Summary Pratical notes

Sectioning Staining and
mounting
Module III
II Sem. B.Sc. Botany



Dr. Sreejith P. E. (IV SEM B. Sc. Notes)

, Sectioning
• Important in histological studies
• Two types
– Free hand sectioning
– Microtome sectioning

I - Free hand sectioning
– A usual method
– But delicate materials should be properly supported
with some materials during sectioning
– Major limitations are
• Extremely small materials can not be sectioned
• Sections may not have uniform size
• Section below 10 microns can not be cut by free hand method
Dr. Sreejith P. E. (IV SEM B. Sc. Notes)

,II - Microtome sectioning (Microtomy)
– Sections are prepared through mechanical cutting device
– Microtome
– Are specially designed to cut away uniformly thin
sections of tissues
– For Electron microscopes extremely thin section are
needed – uses ultramicrotomes
– Common features are,
• Having a feedback mechanism to move the material or cutting
blade forward in a predetermined distance
• A block holder for holding the tissue block
• A knife (cutting blade) holder

Dr. Sreejith P. E. (IV SEM B. Sc. Notes)

, • Microtomes are of two categories
❑The microtome in which the block containing the
material, remains stationary and the cutting knife moves
across it
– E.g., Bench microtome, Clinical microtome, sliding
microtome, sledge microtome etc.
– Not useful in producing serial sections

❑The microtome in which the knife remains stationary
and the block moves across it
– E.g., Rocking microtome, Rotary microtome
– Useful for producing serial sections
Dr. Sreejith P. E. (IV SEM B. Sc. Notes)